Last year, when Billy Connolly learnt he had both prostate cancer and Parkinson's disease, he dealt with the news with his usual comic aplomb: by blowing a raspberry.

Sadly, the British comedian is one of millions of people around the world suffering from Parkinson's, a neurodegenerative condition that causes persistent shaking, gastrointestinal problems and a variety of other ailments.

Now, breakthrough research has brought us closer to understanding how to manage the condition.

Researchers at the University of Technology, Sydney (UTS) led by Dr Dominic Hare and Professor Philip Doble, have produced the first empirical evidence that an imbalance of iron and dopamine in the substantia nigra pars compacta (SNc) region of the brain is the root cause of Parkinson's.

"When these two chemicals react, it forms a toxic species of dopamine that essentially reacts like bleach in the brain," says Dr Hare.

The team used a unique tagging technique deploying antibodies labelled with gold nanoparticles, which acted as proxies for dopamine molecules. This enabled the team to monitor and "co-localise" metals with other molecules and proteins in the brain.

The findings were a revelation.

"Those particular cells (in the SNc) have what you could call an 'anti-Goldilocks effect'. They have just the right amount of iron and just the right amount of dopamine to cause damage," says Dr Hare.

"When we give mice a toxin that mimics the effects of Parkinson's disease, these cells degenerate."

He theorises that this effect is probably a natural result of ageing, when the brain's ability to securely store iron diminishes and allows iron molecules to "leak" into critical areas such as the SNc.

Designing drugs that can get into the brain and eliminate surplus iron is the next step.

Dr Hare is also working on developing preventive measures to halt the build-up of iron in the brain.

"While we might not necessarily find a cure, prevention is actually not that far away," he says.

"So it's a case where you can wake up and say, 'my Parkinson's is flaring up again', take a tablet and go about your business."

This story written and produced by the University of Technology, Sydney, for Brink, a publication distributed monthly in The Sydney Morning Herald.